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This study examines why and when nurses' role ambiguity leads to their work alienation during the COVID-19 pandemic.

Survey data were collected from 335 hospital nurses in Ma’anshan, China. The data were analyzed using hierarchical regression and bootstrapping.

Occupational disidentification mediated the relationship between role ambiguity and work alienation. This mediating effect was not significant when nurses possessed a high level of perceived climate of prioritizing COVID-19 infection prevention (PCIP).

To reduce nurses' work alienation in a pandemic situation, the hospital management team should pay attention to and try to minimize the nurses' role ambiguity and occupational disidentification. When doing so, the management team will find it particularly helpful if they can make nurses perceive a strong climate of PCIP.

This study contributes to the existing knowledge of role ambiguity and work alienation by highlighting occupational disidentification as a mediator after controlling for organizational identification in the context of COVID-19. It further demonstrates when the mediating role of occupational disidentification is likely to be strong or weak by studying the moderating effect of perceived climate of PCIP.

Despite abundant research on the negative effect of gender stereotypes on female leaders, it remains unclear whether leader competence perceived by the subordinates could overcome this backlash effect. Drawing on expectation states theory and expectancy violation theory, the authors investigate how the interaction among leaders' gender roles, leader sex and subordinates' perceived leader competence influences leader effectiveness through subordinates' affective trust.

Data were collected through two-wave surveys among 489 participants from various sectors in different parts of China. SPSS and Hayes PROCESS were used to test the hypotheses.

High competence perceived by the subordinates helps female leaders to overturn the negative effect of masculinity and strengthen the positive effect of femininity, whereas this positive moderation does not hold for male leaders.

This study addresses the ongoing debate about “female advantage” in leadership by showing that female leaders benefit from high perceived competence and are penalized by low perceived competence to a greater extent than male leaders in terms of leader effectiveness.

The material extrusion (ME) process induces variations in the final part’s microscopic and macroscopic structural characteristics. This viewpoint article aims to uncover the relation between ME fabrication parameters and the microstructural and mesostructural characteristics of the ME BASF Ultrafuse Steel 316L metal parts. These characteristics can affect the structural integrity of the produced parts and components used in various engineering applications.

Recent studies on the ME BASF Ultrafuse Steel 316L are reviewed, with a focus on those which report microstructural and mesostructural characteristics that may affect structural integrity.

A relationship between ME fabrication parameters and subsequent microstructural and mesostructural characteristics is discussed. Common microstructural and mesostructural/macrostructural defects are also highlighted and discussed.

This viewpoint article attempts to bridge the existing gap in the literature, highlighting the influence of ME fabrication parameters on Steel 316L parts fabricated via this additive manufacturing method. Moreover, this article identifies and discusses important considerations for the purposes of selecting and optimising the structural integrity of ME-fabricated Steel 316L parts.

The extrusion-based additive manufacturing method followed by debinding and sintering steps can produce metal parts efficiently at a relatively low cost and material wastage. In this study, 316L stainless-steel metal filled filaments were used to print metal parts using the extrusion-based fused filament fabrication (FFF) approach. The purpose of this study is to assess the effects of common FFF printing parameters on the geometric and mechanical performance of FFF manufactured 316L stainless-steel components.

The microstructural characteristics of the metal filled filament, three-dimensional (3D) printed green parts and final sintered parts were analysed. In addition, the dimensional accuracy of the green parts was evaluated, as well as the hardness, tensile properties, relative density, part shrinkage and the porosity of the sintered samples. Moreover, surface quality in terms of surface roughness after sintering was assessed. Predictive models based on artificial neural networks (ANNs) were used for characterizing dimensional accuracy, shrinkage, surface roughness and density. Additionally, the response surface method based on ANNs was applied to represent the behaviour of these parameters and to identify the optimum 3D printing conditions.

The effects of the FFF process parameters such as build orientation and nozzle diameter were significant. The pore distribution was strongly linked to the build orientation and printing strategy. Furthermore, porosity decreased with increased nozzle diameter, which increased mechanical performance. In contrast, lower nozzle diameters achieved lower roughness values and average deviations. Thus, it should be noted that the modification of process parameters to achieve greater geometrical accuracy weakened mechanical performance.

Near-dense 316L austenitic stainless-steel components using FFF technology were successfully manufactured. This study provides print guidelines and further information regarding the impact of FFF process parameters on the mechanical, microstructural and geometric performance of 3D printed 316L components.

Fused deposition modeling (FDM) nowadays offers promising future applications for fabricating not only thermoplastic-based polymers but also composite PLA/Metal alloy materials, this capability bridges the need for metallic components in complex manufacturing processes. The research is to explore the manufacturability of multi-metal parts by printing green bodies of PLA/multi-metal objects, carrying these objects to the debinding process and varying the sintering parameters.

Three different sample types of SS316L part, Inconel 718 part and bimetallic composite of SS316L/IN718 were effectively printed. After the debinding process, the printed parts (green bodies), were isothermally sintered in non-vacuum chamber to investigate the fusion behavior at four different temperatures in the range of 1270 °C−1530 °C for 12 h and slowly cooled in the furnace. All samples was assessed including geometrical assessment to measure the shrinkage, characterization (XRD) to identify the crystallinity of the compound and microstructural evolution (Optical microscopy and SEM) to explore the porosity and morphology on the surface. The hardness of each sample types was measured and compared. The sintering parameter was optimized according to the microstructural evaluation on the interface of SS316L/IN718 composite.

The investigation indicated that the de-binding of all the samples was effectively succeeded through less weight until 16% when the PLA of green bodies was successfully evaporated. The morphology result shows evidence of an effective sintering process to have the grain boundaries in all samples, while multi-metal parts clearly displayed the interface. Furthermore, the result of XRD shows the tendency of lower crystallinity in SS316L parts, whilst IN718 has a high crystallinity. The optimal sintering temperature for SS316L/IN718 parts is 1500 °C. The hardness test concludes that the higher sintering temperature gives a higher hardness result.

This study highlights the successful sintering of a bimetallic stainless steel 316 L/Inconel 718 composite, fabricated via dual-nozzle fused deposition modeling, in a non-vacuum environment at 1500 °C. The resulting material displayed maximum hardness values of 872 HV for SS316L and 755.5 HV for IN718, with both materials exhibiting excellent fusion without any cracks.

This study aims to deepen the knowledge concerning the metal fused filament fabrication technology through an analysis of the printing parameters of a commercial 316L stainless steel filament and their influence on the porosity and mechanical properties of the printed parts. It also investigates the feasibility of manufacturing complex geometries, including strut-and-node and triply periodic minimal surface lattices.

A three-step experimental campaign was carried out. Firstly, the printing parameters were evaluated by analysing the green parts: porosity and density measurements were used to define the best printing profile. Then, the microstructure and porosity of the sintered parts were investigated using light optical and scanning electron microscopy, while their mechanical properties were obtained through tensile tests. Finally, manufacturability limits were explored with reference samples and cellular structures having different topologies.

The choice of printing parameters drastically influences the porosity of green parts. A printing profile which enables reaching a relative density above 99% has been identified. However, voids characterise the sintered components in parallel planes at the interfaces between layers, which inevitably affect their mechanical properties. Lattice structures and complex geometries can be effectively printed, debinded, and sintered if properly dimensioned to fulfil printing constraints.

This study provides an extensive analysis of the printing parameters for the 316L filament used and an in-depth investigation of the potential of the metal fused filament fabrication technology in printing lightweight structures.

The finite-time visual servoing control problem is considered for dynamic wheeled mobile robots (WMRs) with unknown control direction and external disturbance.

By using finite-time control method and switching design technique.

First, the visual servoing kinematic WMR model is developed, which can be converted to the dynamic chained-form systems by using a state and input feedback transformation. Then, for two decoupled subsystems of the chained-form systems, according to the finite-time stability control theory, a discontinuous three-step switching control strategy is proposed in the presence of uncertain control coefficients and external disturbance.

A class of discontinuous anti-interference control method has been presented for the dynamic nonholonomic systems.

During the early 1970s, faced with the serious demographic situation, China began to fully implement the policy of family planning in urban and rural regions. Nowadays, the problems of pension and medical care for aged parents confronted by the first generation of the one‐child family have begun to gradually appear. Meanwhile, China's population and the family planning are also faced with some problems that are difficult to solve, including unbalanced fertility rate of urban and rural population, the gender imbalance, the difficulty of the risk diversification in a one‐child family, as well as the profound contradiction between the stability of the family planning policy and the drive of administrative measures. Therefore, it is necessary to establish the integrated‐scheduled life security system of the one‐child family in urban and rural areas, in order to overcome the problems and to promote the transformation of the family planning policy. The purpose of this paper is to discuss the life security system for China's one‐child families.

The life security system for the one‐child family proposed by this paper consists of three issues: the basic security based on the level of social security, the additional security of the policy insurance and the supplementary security of the commercial insurance. The paper begins with the history of the family planning policy in the first section and then go through some relevant articles regarding complementary measures such as maternity insurance, rural endowment insurance that only focused on one aspect of issues associated with the family planning. In section three, four typical problems are listed for the purpose of following discussion of corresponding solutions which are full of deficiency in section four. In part five, the integrated planning of the life security system for Chinese one‐child family is elaborated with risk and fund management. In the last part, we conclude that the family planning policy maintains stable, whereas measures to be taken are adjusted along with changeable new problems.

The policy insurance plays an increasingly important role in dealing with the life security of older people in one‐child families. It may be better to promote the kind of insurance.

The paper comprehensively discusses the life security system for Chinese families in compliance with the family planning policy.

This study aims to research the development trend, research status, research results and existing problems of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

Based on the investigation and analysis of the development history, structure form, structural parameters, stress characteristics, shear connector stress state, force transmission mechanism, and fatigue performance, aiming at the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge, the development trend, research status, research results and existing problems are expounded.

The shear-compression composite joint has become the main form in practice, featuring shortened length and simplified structure. The length of composite joints between 1.5 and 3.0 m has no significant effect on the stress and force transmission laws of the main girder. The reasonable thickness of the bearing plate is 40–70 mm. The calculation theory and simplified calculation formula of the overall bearing capacity, the nonuniformity and distribution laws of the shear connector, the force transferring ratio of steel and concrete components, the fatigue failure mechanism and structural parameters effects are the focus of the research study.

This study puts forward some suggestions and prospects for the structural design and theoretical research of the steel–concrete composite joint of railway long-span hybrid girder cable-stayed bridge.

This paper aims to analyze the situation of knowledge dissemination in Chinese rural areas and explore factors that affect the efficiency of knowledge dissemination, to provide some suggestions for further improvements.

A survey was conducted to collect data in 17 provinces of China, with 267 questionnaires returned out of 300. Structural equation modeling was used to test the hypothesis with LISEREL 8.8.

The results show that factors of knowledge such as government participation, dissemination capability, learning motivation and trust have a positive effect on knowledge transfer. By contrast, factors of knowledge such as complexity and richness of knowledge carriers do not have a significant correlation with the knowledge sharing level.

This paper conducts a cross-sectional analysis while ignoring the longitudinal effects of some factors on knowledge dissemination, such as the reform and opening policy in China. An analysis on a more concrete problem could be conducted for future study.

This paper proposes some suggestions to enhance the efficiency of knowledge dissemination in rural areas from the knowledge dissemination mode, knowledge products and the role of government playing.

This paper is among the first attempts to conduct comprehensive and systematic research on the influential factors of knowledge dissemination. It contributes to literature by offering a systematical empirical study with the consideration of the role of government in knowledge dissemination.